Remove hybi sub directory for WebSocket layout tests

LayoutTests/http/tests/websocket/unmasked-frames_wsh.py

 from mod_pywebsocket import common
 from mod_pywebsocket import handshake
 from mod_pywebsocket import stream
 from mod_pywebsocket import msgutil
 
 
 def web_socket_do_extra_handshake(request):
     pass
 
 
@@ skipping 15 matching lines @@
     assert final
     assert not reserved1
     assert not reserved2
     assert not reserved3
 
     # Send a masked close frame. Clients should be able to handle this frame and
     # the WebSocket object should be closed cleanly.
     request.connection.write(stream.create_close_frame('', mask=False))
 
     raise handshake.AbortedByUserException('Abort the connection') # Prevents pywebsocket from starting its own closing handshake.